


After the end of the world

by Romanceiscool



Category: Undertale (Video Game)
Genre: Alternate Universe, Alternate Universe - Zombie Apocalypse, Fontcest, Gay, Kedgeup, M/M, Other, Papster - Freeform, Papyster, Polyamorous Character, Polyamory, Possible Character Death, Sanscest - Freeform, Swapfell Sans (Undertale), Underfell Papyrus (Undertale), Underfell Sans (Undertale), Underswap Papyrus (Undertale), Zombie Apocalypse, hints of kustard, kustard - Freeform, papcest - Freeform
Language: English
Status: In-Progress
Published: 2019-05-04
Updated: 2019-07-18
Packaged: 2020-02-21 17:27:18
Rating: Mature
Warnings: Graphic Depictions Of Violence, Major Character Death
Chapters: 4
Words: 4,213
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/18706978
Author URL: https://archiveofourown.org/users/Romanceiscool/pseuds/Romanceiscool
Summary: It's been 3 long years since the war between humans and monsters occured. Monsters were feared after finding out what they were able to do and the power they could have over the humans, therefore lead to the unforgiving war. It started off as any other normal war could...bloodshed, attacks, strategy..that is until the humans tried to make a weapon. They thought making a new creature would scare off the monsters enough to leave them alone. They wanted to make living dead creatures, but...the experiment failed. Before they knew it, both monster and human lives were threatened by these undead creatures. Many people have lost their lives..but many are still fighting to keep their lives for as long as possible.





	1. A new day

Sans hummed to himself quietly as he waited for his brother to be done with the food. This cabin has probably been the safest place they've been in for a long while...well for now anyways. You can imagine how excited him and his brother were to have finally found some food! A few cans of food was all they were able to get, but at least they got something. Red of course was a little..less excited by this. Considering he didn't think this would even last them a week, but he always thought nothing was enough...though they supposed he was in a way right. They needed something to last them a lifetime in this kind of world. Sans and Papyrus had found red alone in a shack surrounded by the undead. Them and their group were able to get rid of as much as possible and got him out of their. Though that was long ago when their group was much bigger...at the moment it was down to only 5 of them. Red, Sans, Papyrus, Rass, and Stretch...let's just say an accident at the old camp caused them to lose about 10 members of their once large group. Rass was a bit antisocial when it came to them all now, the only reason he ever joined their group was that his brother, Slim, needed help but...they had lost slim long before losing the others and he seemed to still not be over it. Stretch could relate to him since he sadly lost his little brother Berry when the accident occurred. He never took off the bright cyan scarf and everyone was guessing he never planned on doing so. Sans and Papyrus luckily stood together through it all, and were able to escape with the other 3. As for red...well he had no idea what happened to his brother. When they found him in the shack, he had told them that he had been separated from his brother after a wave passed by and he hasn't seen him since.

"Yo, how long is the food gonna be?" Stretch asked as he played around with his little switchblade. Papyrus huffed "It'll be done when i say so! Be patient". "Not everyone can be patient when ya haven't eaten for 2 days" a familiar voice said with Their usual New york accent. It was red, he had just gotten back with Rass from scavenging for a bit. They all took turns doing so, but they never really let sans go out unless it was with at least 2 of the others. Sans really appreciated how the others well..cared for him, but he was just as strong as they all were! None of them seemed to believe that because of his sweet nature, even though most of them have stuck with him for more than a year..and when it came to his brother, all 3 years. "Well I'll try to be as quick as possible! i know we're all hungry, but this takes time!" papyrus said simply. Rass rolled his eyes at all this bickering and decided to head back out to keep watch as usual. Sans was actually kind of worried about him...he usually never rests or relaxes much.. hopefully he could take his shift after dinner or something. After a while, dinner was finally done. Papyrus had found some cardboard boxes which were a pretty good replacement for plates and he served everyone on the dinner table that they had here. It was actually... quite calming here. Stretch went out and called rass for dinner and he reluctantly walked into the cabin to join the others. “Alright, what are we eating?” He asked softly. It was probably the first things he said to them today. “For dinner I made us all some rabbit!” papyrus said with a smile. “Rabbit? How many didja find?” Red asked with a yawn. “About 4 of them actually!” Papyrus said with a successful smile. They all began to eat and sans sighed with relief “god it's so good to eat again..” he said softly as he hummed. Everyone seemed to agree at that. “Hey! When me and rass went out scavagin’ we found some o’ these” he said as he pulled out a few packets of vegetable seeds. Sans gasped “o-oh my God! You were actually able to get these???” He asked and red smirked “i knew ya liked planting and we needed the veggies...sooo...anything for you baby~” he said with a wink and sat back. Sans blushed slightly “..uh..thank you??” He said shyly. Papyrus gave red a glare...he knew that red wasn't actually into his brother, but did he HAVE to flirt with him and the others almost all the time?? Sans rolled his eyes and giggled “still this is great! I can get to work with these when I can!”. “We also found a little campground just a few minutes from here too...from afar at least” rass said quietly as he ate. Stretch raised a brow “really? How many people did it look like where there??” He asked. Red shrugged “one maybe? Dunno, but we should keep an eye out for whoever it is” he said with his mouth full. The others agreed “maybe I can go out tomorrow and check it out..anyone wanna come with..not you” he said to sans as he was about to ask. Sans huffed and sighed disappointedly. “I'll go” red said with a smirk. “And babe don't worry..if ya ever come along on our trips, just know ya got a nice strong man to protect ya~” he said with another wink..which caused him to get elbowed by sans himself. Sans was no damsel in distress! He could take care of himself and others just fine >:///T…”well..for now we should head to bed...stretch you're on night shift tonight, you kissed 2 times of doing so” he said sternly. Stretch chuckled and nodded “yes sir” he said and grabbed his switchblade and his revolver just in case. The others said their goodnights and went to bed ..cept rass cause he had to sharpen his spear before he went to bed every night...it's like a part of his schedule?? Well... until then, red and papyrus were fast asleep, getting energy to head out tomorrow and figure something out about that small camp.


	2. Someone New

Papyrus and Red were making their way to where he and rass saw the little camp. Red stopped papyrus before he could go on further, he pointed in the direction of the string with some cans attached to it. Papyrus figured it was so that if anything or anyone came near the camp, the person here would be able to hear it. Papyrus thanked red quietly and as quietly as possible went over it. "Alright...I'll go around to the other side...make sure to stay out of view and if something goes wrong then drop your weapon as hard as possible so i can hear it, ok?" Papyrus said. Red nodded and stayed in place. Papyrus went around the camp and saw a small fire cooking up a can of beans... Hmm...this person was still here yet he saw no one in sight. Papyrus sighed and stepped before yelping as a strong rope tied around his ankle tightly and raised him up. He groaned as he was now hanging upside down. "G-god dammit!" He whispered. Red heard the yelp and became alerted but hid as he saw someone walking towards papyrus...oh no. The tall man seemed to be about papyrus' height. He wore a leather jacket and leather pants, but was wearing some sort of hoodie. He leaned down and held a knife to Papyrus face "what do you want?" He growled deeply. Papyrus shook and tried to reach for his gun but the man quickly took that and his kitchen knife "i said...what do you want!?" He growled and papyrus groaned "i-i was just trying to get by!" He said but the man pressed the knife closer to his neck "that's a lie...you wouldn't have gotten trapped if you were just...trying to get by" he said and rolled his eyes. He stood back up and and scoffed "i swear i have no idea how idiots like you stay alive this long.." He muttered making papyrus growl a bit "you know you should really watch what you say...you don't know who you're dealing with out here and that smart mouth of yours could get you in a lot of trouble.." He said which got him a glare from the man. "..excuse me?" He hissed angrily causing papyrus to shake a bit ok this guy really intimidated him just by his looks alone. Man, him and his big mouth. Red watched this all go down and tried his best to go behind the man as quietly as possible.he could swear that voice sounded a little familiar and just...he felt some strange connection just by looking at the dude but he couldn't put his finger on it. Red shrugged and pulled out his bow and aimed it at the man's back but accidentally brushed against a bush. The man froze as he heard a rustle behind him. He growled and grabbed his bat from his back pack before turning around and getting ready to swing. He then froze and stared at red who had his bow and arrow aimed at him "don't move.." He said before realizing the man had frozen. Red raised a grow but kept his stance...the man then shook before grabbing his hoodie and taking it off "....red?" He said before Red eyes widened…

"...bro?"

**Notes for the Chapter:**

> Author's Note: sorry that this chapter is short!! I wanted to post this as fast as possible! I dont like waiting too long to post!


	3. A New "Friend"

**Summary for the Chapter:**

> Who was that strange man that papyrus and rwd found?? Well you're about to find out more about him in this chapter!!

"..bro...i..oh thank the stars!" Red said and pulled his brother into a tight hug. The man did the same and papyrus cleared his throat and red blushed "oh! Papyrus! This is my brother, Edge!" Red said with a smile and papyrus cleared his throat louder causing red to raise a brow. "Oh! Right, sorry" he said before grabbing a knife to cut him down before edge grabbed red's arm. "...you know this man?.." He asked and gave papyrus a glare making papyrus gulp. Red nodded "yeah, i do. He's a good guy edge! I promise" he reassured causing edge to huff a bit "fine...but if he tries anything on me i'm killing him instantly" he hissed and papyrus growled a bit before yelping as red cut him down and he fell down, letting out a groan "wow. thanks." Papyrus growled, making red chuckle a bit. "Yeah yeah whateva'...bro we got a small cabin naht too far from here! You should come with us!" He said and papyrus froze "what??? No way! What if he does something to the others?? I'm especially not letting him near my brother!" He said and Edge glared at him "Well now i know that your people might be weak. Brother i appreciate the offer but i rather be with a strong group" Edge said, papyrus was much too protective. That must have meant that it was because his group was weak! Red shook his head "nah! Trust me bro we got a strong group!" He said "please! C'mon i haven't seen ya in so long i….i don't wanna lose ya again..". Edge stared at red a bit but sighed "fine.." He said and papyrus crossed his arms. "I said. No." He reminded but red glared at him "buddy, if you lost yer brother fer almost a year, then maybe you wouldn't be so damn rude" he growled and papyrus sighed...he...supposed ge was right. "Fine...but if he hurts ANYONE in the group...i swear-" he said before edge rolled his eyes "as if i'd waste my time like that" he growled and papyrus gave him another glare. 

Sooner or later the 3 returned to the cabin..Papyrus decided he'd enter first and that Edge would come in last, he wouldn't want his group freaking out that some stranger was here. He knocked on the door and Stretch was the one to answer "oh hey! You took a while..i- uhm i mean..WE..were starting to get a little worried" he said gently with a smile as he blushed. Papyrus raised a brow but shrugged it off "we're both fine we just uh..found something. Not a great find but it's something" he said making edge huff from afar. "Well uh...im so glad you're ok..er both of you that is!!" Stretch said and blushed more. Papyrus blinked….oookay "well...we all need to talk so if you could get everyone to the living room that would be great" he said and Stretch went to do just that. He signaled to red and edge to get ready as he walked into the cabin. Rass, sams, and stretch were all in the living room now, confused and curious as to what was going on. "Is everything ok??" Sans asked softly and Papyrus hummed "Yes...everything is fine but uh..while we were out scavenging we found something." He said with a light look of distaste before red came in as well "Someone actually" he said before pulling his brother into the living room. Edge stared at them coldly amd sans squeaked "w-who is that????" He asked nervously. Rass growled and pulled out his spear "Ya better back off" he said as he pointed his weapon at edge. Edge raised a brow and red pulled the weapon a way "woah woah! Calm down guys! This is my brother edge!..ya know. The one that i got seperated from!" He reminded and Stretch stared up at him a bit...he was a little taller than him but also a little shorter than papyrus..and he looked intimidating as hell with uis leather jacket and those two scars running down his left eye..not to mention his sharp teeth. Edge observed everyone in this room and looked at sans who seemed to be shaking a lil "...im assuming you're the runt? Small...and weak" he said and.walked closer to him, Sans did seem to be the smallest and more fearful one. Papyrus moved in front of his brother and growled at edge "Back off.." He growled making edge stand back a little "i Was being honest...it's easy to tell when someone is.." He said and.glanced at sans a bit "..clearly weak" he said and sans huffed a bit at that. Rass wasn't very happy with all this...at all. "You better watch yourself. If you're gonna be staying here..you have to go by OUR damn rules" he said and looked at red "And that means we aren't treating him all buddy buddy here either." He stated. "You're lucky we have an extra bedroom..but maybe we should just make you sleep on the couch anyway.". Edge rolled his eyes "I've slept on a floor before i don't care where the fuck you put me" he said and Red stopped them both "guys! C'mon...can't we at least TRY to get along! I know y'all dont know eachother...but edge..I've been these guys fer a whole year now and...i trust 'em. And guys..this is my BROTHER...the guy i spent most of my life with so far!" He said and Everyone grew silent…."...we could try giving him a chance…" Sans muttered quietly and papyrus looked back at him "...whatever. Let red take you to your room..I'm going outside on watch" he growled before leaving. "Papyrus hold up!" Stretch said as he followed him out. Red sighed "i'm...sure they'll warm up to ya soon" he said to edge. "I dont care...im only here for you anyway" Edge said honestly before sans walked over to edge nervously "uh….do you...want any uhm...food or..anything?..." He asked anxiously and edge raised a brow "...sure." He said simply and went to go sit on the couch. Red could already tell that...this was gonna be a looooong day.

**Notes for the Chapter:**

> Sorry for take so long to post!! I was afraid no one was gonna be too into it!


	4. Bonding!(?)

**Summary for the Chapter:**

> Red sends his brother and papyrus out to scavange!! What could possible go wrong while they're out??

It had been a few days since edge had gotten here. He seemed to only be talking to red or sans, Though sans was usually pretty scared of the guy, but he was luckily getting used to it. Though that didn't seem to stop papyrus from keeping an eye on him, or keeping him away from his brother in general. If anything, those two were the ones who were fighting the most at all times. Red was getting slightly annoyed with it from time to time, especially since it was constant yelling about the same damn things. Well red had enough of it!! He was gonna get these two to get a long (or at least to shut up) no matter what!! So he designed a trip for these two..yeah...he was gonna send them out for a little scavenging. He knew papyrus was basically the leader of the group, but he already figured a plan and luckily both stretch and rass were going along with it. He may not like edge, but he was getting really annoyed too. Red hummed as he walked over to papyrus "hey dude, i promised edge that I'd give him something to do. Ya got anything open??" He asked. Papyrus huffed "only scavenging. But Someone has to go with him!! I don't want him bringing home another group to kill us all." He growled. Red smirked "ah shit... I'd go with him, but I'm on fishing duty with rass today." He hummed. Papyrus rose a brow "maybe you can ask stretch" he said and red shook his head "he's busy with guarding the place. Hm..maybe sans isn't bus-". "I'LL GO." Papyrus growled quickly. No way was he letting sans go alone with that asshole. He could hurt him!!...or worse. Red tried to hold back a smile. "Oh shit, really?? Alright I think that's best. Just don't be too hard on him, K?? The dudes really good at what he does" he said but papyrus rolled his eyes. "Yeah yeah. Just go tell him to get ready or I'm leaving without him." Papyrus huffed as he crossed his arms before going to his room to get ready. Red hummed and walked over to edge, who at the moment was in the kitchen eating. He usually ate after everyone else did to be left alone. "Hey bro!" Red said with a smirk. Edge looked at his brother with slight suspicion "what do you want." He simply said. "Whaaat? I can't say hey to my own brother??" He asked with a fake lil smile. Edge rolled his eyes "hello. Now what do you want??" He asked. Red hummed "i just wanted to tell you to get ready. Papyrus is taking you out scavenging!" He hummed with a (slightly evil) smile. Edge froze and coughed up his food "what?!? No fucking way am I going with that ignorant idiot!!" He scowled. Red flinched "woah!! Calm down, bro! C'mon it's just for a while! Get it over with!!" He insisted. Edge groaned. "Whatever. I'll be in my room getting ready for a trip with Satan himself" he huffed, making red laugh a bit. "He ain't that bad bro" he tried to reassure him. "Maybe not to you, but when it comes to others I'd say otherwise" Edge muttered before heading into the bedroom he was assigned to. Red watched as his brother  into his room before sighing. He hoped this would get the two to get along. He didn't want edge feeling like more of an outcast than he already was. After a while Both edge and papyrus were out of their room, lightly glaring at each other now and then. "Now edge, you shall follow MY orders. Whatever I say, goes. Unless you plan on dying to those creatures." Papyrus huffed sternly. "No way, I don't take orders from anyone. Especially not lousy leaders" he growled making papyrus glare at him. Red cleared his throat "guys! Calm down! Here just..take some food and I got all your shit ready to head out." he sighed. Sans peeked in and looked at the two. He shook on slightly when he saw edge,though not as much as when they first met. Edge seemed like a pretty decent guy but man he was still intimidating. He gave them both a small smile "B-be safe o-out there, b-both of y-you" sans said sweetly. Papyrus sighed and smiled "Thank you, brother. And just because I'm gone does NOT mean you can go out" he huffed making sans puff up his cheeks. Edge cleared his throat "uh...thank you" he muttered. Sans sighed "of c-course. I'll s-see you b-both later" he said with another sweet smile before going back into the other room. Red hummed as he watched sans leave. "You guys take yer time out there, ya know the rules, No coming back unless things go bad or if ya find something" he chuckled. They both nodded and began to make their way out while red went over to...talk to sans. Edge and Papyrus walked for quite a while in absolute silence, not wanting to even try and converse with each other. "...So I figured we head east" edge said suddenly, making papyrus jump a bit. "And since when did we take YOUR orders??" Papyrus groaned. Edge rose a brow "well let's see...if you hadn't taken notice, a possible swarm could be coming from the West, the river is north and south is just heading back home, so where would you like to go genius??" He growled. Papyrus blinked before clearing his throat "uhm...anyway!! I say we head east!" He hummed as he walked ahead, making edge snarl behind him. They began to head east, edge mostly keeping guard while papyrus made sure they were going in the right direction. "So...where exactly are we going?" Edge asked and papyrus shrugged "hopefully we'll find a store or a small town nearby to get some supplies...I don't wanna run I to anything else." Papyrus said. "Oh, I definitely hope we do." Edge said sarcastically, which earned him a glare from papyrus. "Ok smartass, let's just make sure we don't get lost." Papyrus growled as he kept walking. They kept walking before papyrus suddenly stopped, making edge bump into him. "Dude what the fu-!?" Edge tried to scowl before papyrus quickly raised his hand to his mouth. "Shut up for a second." He said quietly. Edge blinked before going silent as he tried to listen for whatever the hell it was papyrus was hearing. Suddenly a bullet was shot but luckily it missed them both. "SHIT!!" Papyrus growled before grabbing edge's shoulder and pulling him down behind the rock. Bullets began flying through the air, clearly being aimed towards.  "You know how to shoot a gun???" Papyrus ask quickly but before edge could answer he quickly tossed him a gun. Papyrus waited for his chance before coming up and shooting at the direction. He heard some yelling and a man groaning, seemed he got a shot. Edge froze as he heard the voice yelling "we need to get out of here now-!" He said before papyrus got shot in the arm "FUCK!!!" Papyrus yelled in pain. "WHAT'RE YOU DOING?! FUCKING SHOOT!!" he yelled. Edge muttered under his breath before moving into position and shooting. It wasn't as precise as papyrus but he did get a few shots to some dudes. "Follow me!!" Edge said as he helped papyrus up and he began running. Papyrus made sure to follow behind him as they kept running. "Where are we going???"" Papyrus asked. "I don't know but away from there!!" Edge huffed. As they ran they found a building and edge quickly lead papyrus into it before taking him upstairs as he lightly panted. "Are you alright??" Edge asked. "Oh yes getting shot in the arm makes me feel just PEACHY!" Papyrus growled and Edge seemed a little taken aback. "Calm the fuck down, I just wanted to fucking ask!" Edge yelled angrily. Just then they heard the door from downstairs open and they both began to hide behind a desk that was in the room. It seemed that this used to be some sort of small office. Edge heard the familiar barbed wire covered bat scraping against the floor. He let out a quiet groan which caused papyrus to give him a look. "..i feel like you're not telling me something.." papyrus said quietly. Edge paused for a bit before looking away in silence. "Eeeedge?~ Is that you buddy??? That yelling sure did sound familiar!!" A man with a deep and rugged voice said, the familiar tone echoed through edge's skull as he bared his teeth and clenched his fists. Papyrus stared at edge more...what was he hiding from him...was this his group??....had edge been lying to them the whole time…?? Out of anything, edge definitely didn't expect this. He felt a gun being pointed against his head. He looked before seeing it was papyrus, a calmly pissed expression on his face. ".....who are these people?"


End file.
